Study of normal liquid 3He using the method of collective description of interparticle interactions and a realistic form of two-body potential

Abstract

Visualizing 3He liquid at zero temperature as an interacting system of quasi-particles and the quanta of its zero-sound mode, calculation of the binding energy of the system in its normal phase is made using many-body techniques with a realistic form of interparticle potential constituting both repulsive and attractive components. The new potential has a form similar to the Walecka potential used by us some time back in the study of nuclear matter, and unlike the Lennard–Jones potential, which is most commonly used for liquid 3He, it has a Fourier transform. The calculated binding energy per particle in liquid 3He is found to be −2.478 K, which exactly agrees with the experimental result −2.48 K. This shows a substantial improvement over our earlier result obtained for a contact form of interparticle potential. For the new potential, we arrive at a velocity of 203.8 m/s for the zero-sound mode by following a self-consistent method of calculation, which is close to the experimental value of 194.4 m/s obtained by Abel et al. (Phys. Rev. 147 (1966) 111). By accounting for the local field corrections, beyond the random-phase approximation, to the bare particle-hole propagator in a parametric way, we exactly reproduce the experimental result for the zero-sound mode. The present calculation also indicates the propagation of a new kind of sound wave in liquid 3He at T=0 K, with a velocity of 153.7 m/s, similar to the one found in an earlier calculation.